1. Field of Invention
This invention relates generally to three-dimensional object representations and more particularly to producing a representation of a mold for forming an appliance for a living body.
2. Description of Related Art
Prostheses and orthoses are commonly produced from three-dimensional representations of a body part of a human or an animal. The three-dimensional representation may then be used to produce instructions for controlling a carving machine that is configured to carve a three-dimensional reproduction of the body part from wood or a synthetic material such as a polyurethane block.
The three-dimensional reproduction of the body part may then be used to produce an appliance to meet a patient's specific needs. For example, the three-dimensional reproduction may be used directly to produce a prosthesis, or indirectly as a mold for forming a molded orthosis. An orthosis is an appliance that is applied externally to a body part to correct deformity, improve function, or relieve symptoms of a disease by supporting or assisting the musculo-neuro-skeletal system. A prosthesis is an appliance that replaces a missing body part.
The three-dimensional representation of the body part may be produced using a non-contact optical scanner that images the body part with a high level of accuracy. The scanner may include a laser for illuminating the body part with structured light and a video camera for capturing images of the illuminated body part. The captured images may then be processed to extract three-dimensional coordinates of the surface of the body part, which may be used in turn to produce the appliance.
When producing such appliances, and in particular when producing orthoses, it may be desired to flare some of the edges of the appliance to reduce chafing and/or abrasion at the edge. Flared edges have been produced by attaching protrusions onto the three-dimensional reproduction in the vicinity of a desired edge to flare the edge of the molded appliance. Placing and attaching the protrusions is a manual task which is subject to operator error and may result in incorrectly positioned or incorrectly shaped flares in the appliance.
There remains a need for better methods and apparatus for producing appliances for a living body part.